01 -
Place frozen white bread loaf in a greased bowl covered with plastic wrap. Let rise in a warm area until dough is fully thawed and has doubled in size, approximately 2 to 3 hours.
02 -
Dice bell pepper and onion, and thinly slice mushrooms. Heat 1 tablespoon butter in a skillet over medium heat. Sauté vegetables until softened and lightly browned, about 6 minutes. Remove from heat and cool slightly.
03 -
Set oven temperature to 375°F. Line a baking sheet with parchment paper or spray with cooking spray for easy removal.
04 -
On a lightly floured surface, roll the risen dough into a 12 by 18 inch rectangle, maintaining even thickness without tearing.
05 -
Combine mayonnaise and garlic powder in a small bowl, mixing thoroughly. Spread evenly across the dough surface, leaving a 1/2 inch border around edges.
06 -
Arrange sliced roast beef evenly over the mayonnaise layer. Distribute sautéed vegetables evenly on top. Finally, layer provolone cheese slices to cover, overlapping if necessary.
07 -
Starting from one long edge, tightly roll the dough like a jelly roll. Tuck fillings in as needed. Pinch seams and ends firmly to seal.
08 -
Place the roll seam-side down on the prepared baking sheet. Melt remaining butter and brush generously over the top. Sprinkle with garlic salt, sesame seeds, and dried parsley evenly.
09 -
Bake in the preheated oven for 15 to 20 minutes, until crust is golden brown and internal temperature reaches 165°F.
10 -
Remove from oven and allow the stromboli to rest for 5 minutes to set. Slice with a serrated knife and serve warm.